Usefulness of Testing in existing project

[AnilPrakash Raju]

Hi Lasse,
How useful is the book in applying Testing on existing projects? i am working on an existing project, but doing some enhancements to the project

thanks

Anil

[Lasse Koskela]

Hi Anil,

Originally posted by AnilPrakash Raju:
How useful is the book in applying Testing on existing projects? i am working on an existing project, but doing some enhancements to the project

Part 2 of the book is useful for a Java EE developer not just in learning to use TDD but also for learning how to write tests for various Java EE components. Part 3, on the other hand, talks a lot about system level test automation, which can also be useful from a pure "testing" perspective.

[Ilja Preuss]

In my experience, enhancing an existing system always can be done at least partly in a way that allows adding new code that is reasonably decoupled from the already existing code. For that part of the code, TDD can be a applied just as when working on a greenfield project.

Writing tests for already existing code is harder and requires additional skills. I'd advise to ignore that part for the moment and get good at the above (which I'd assume Lasse's book is appropriate for). Once have grip on doing TDD for new code, you might want to take a look at the book "Working Effectively With Legacy Code".

[Paul Croarkin]

In addition to "Working with Legacy Code", I'd recommend Martin Fowler's "Refactoring" book.

[Ilja Preuss]

Originally posted by Paul Croarkin:
In addition to "Working with Legacy Code", I'd recommend Martin Fowler's "Refactoring" book.

Yes, that's definitely a required read, even without legacy code or TDD at all (although it will be a big help with both).

[Stefan Bell]

Originally posted by Paul Croarkin:
In addition to "Working with Legacy Code", I'd recommend Martin Fowler's "Refactoring" book.

One of the best books ever. I would make that book required reading for all developers.